3Com Corporation
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gateway:
A gateway is a network point that acts as
an entrance to another network. On the Internet, a
node or stopping point can be either a gateway
node or a host (end-point) node. Both the
computers of Internet users and the computers that
serve pages to users are host nodes. The
computers that control traffic within your company's
network or at your local Internet service provider
(ISP) are gateway nodes.
H
hot-spot:
A hot-spot is wireless public access
system that allows subscribers to be connected to a
wireless network in order to access the Internet or
other devices, such as printers. Hot-spots are
created by WLAN access points, installed in public
venues. Common locations for public access are
hotels, airport lounges, railway stations or coffee
shops.
hot-spot operator:
An entity that operates a facility
consisting of a Wi-Fi public access network and
participates in the authentication.
HTTP:
The Hypertext Transfer Protocol (HTTP) is
the set of rules for exchanging files (text, graphic
images, sound, video, and other multimedia files)
on the World Wide Web. Relative to the TCP/IP
suite of protocols (which are the basis for
information exchange on the Internet), HTTP is an
application protocol.
HTTPS:
HTTPS (Hypertext Transfer Protocol over
Secure Socket Layer, or HTTP over SSL) is a Web
protocol developed by Netscape and built into its
browser that encrypts and decrypts user page
requests as well as the pages that are returned by
the Web server. HTTPS is really just the use of
Netscape's Secure Socket Layer (SSL) as a
sublayer under its regular HTTP application
layering.
I
ICMP:
ICMP (Internet Control Message Protocol) is
a message control and error-reporting protocol
between a host server and a gateway to the Internet.
ICMP uses Internet Protocol (IP) datagrams, but the
messages are processed by the IP software and
are not directly apparent to the application user.
IEEE:
Institute of Electrical and Electronics
Engineers. The IEEE describes itself as the world's
largest professional society. The IEEE fosters the
development of standards that often become
national and international standards, such as
802.11.
IP:
The Internet Protocol (IP) is the method or
protocol by which data is sent from one computer to
another on the Internet. Each computer (known as a
host) on the Internet has at least one IP address
that uniquely identifies it from all other computers
on the Internet. When you send or receive data (for
example, an e-mail note or a Web page), the
message gets divided into little chunks called
packets. Each of these packets contains both the
sender's Internet address and the receiver's
address. Any packet is sent first to a gateway
computer that understands a small part of the
Internet. The gateway computer reads the
destination address and forwards the packet to an
adjacent gateway that in turn reads the destination
address and so forth across the Internet until one
gateway recognizes the packet as belonging to a
computer within its immediate neighborhood or
domain. That gateway then forwards the packet
directly to the computer whose address is specified.
IPsec:
IPsec
(Internet Protocol Security) is a
developing standard for security at the network or
packet processing layer of network communication.
Earlier security approaches have inserted security
at the application layer of the communications
model. IPsec will be especially useful for
implementing virtual private networks and for
remote user access through dial-up connection to
private networks. A big advantage of IPsec is that
security arrangements can be handled without
requiring changes to individual user computers.
Cisco has been a leader in proposing IPsec as a
standard (or combination of standards and
technologies) and has included support for it in its
network routers.
IPsec provides two choices of security service:
Authentication Header (AH), which essentially
allows authentication of the sender of data, and
Encapsulating Security Payload (ESP), which
supports both authentication of the sender and
encryption of data as well. The specific information
associated with each of these services is inserted
into the packet in a header that follows the IP packet
header. Separate key protocols can be selected,
such as the ISAKMP/Oakley protocol.
ISP:
An ISP (Internet Service Provider) is a
company that provides individuals and other
companies access to the Internet and other related
services such as Web site building and virtual
hosting. An ISP has the equipment and the
telecommunication line access required to have a
point-of-presence on the Internet for the geographic
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